Specify color in RGB in the docs about the new NumPy logo

Specifying color in RGB in the guidelines for the new NumPy logo. Fixes #numpygh-398 numpy/numpy.org#398

Author: aerikpawson

branding/logo/logoguidelines.md

@@ -4,7 +4,7 @@ These guidelines are meant to help keep the NumPy logo consistent and recognizab
 The primary logo is the horizontal option (logomark and text next to each other) and the secondary logo is the stacked version (logomark over text). I’ve also provided the logomark on its own (meaning it doesn’t have text). When in doubt, it’s preferable to use primary or secondary options over the logomark alone.
 
 ## Color
-The full color options are a combo of Maximum Blue (#4DABCF) and Han Blue (#4D77CF), while light options are white (#FFFFFF) and dark options Warm Black (#013243).
+The full color options are a combo of Maximum Blue/rgb(77, 171, 207) and Han Blue/rgb(77, 119, 207), while light options are White/rgb(255, 255, 255) and dark options are Gunmetal/rgb(1, 50, 67).
 
 Whenever possible, use the full color logos. One color logos (light or dark) are to be used when full color will not have enough contrast, usually when logos must be on colored backgrounds.
 
@@ -15,4 +15,4 @@ Please do not make the primary logo smaller than 50px wide, secondary logo small
 A few other notes to keep in mind when using the logo:
 - Make sure to scale the logo proportionally.
 - Maintain a good amount of space around the logo. Don’t let it overlap with text, images, or other elements.
-- Do not try and recreate or modify the logo. For example, do not use the logomark and then try to write NumPy in another font.
+- Do not try and recreate or modify the logo. For example, do not use the logomark and then try to write NumPy in another font.